Motor belt-tensioning appliance



29, 1924': P. SPILGER MOTOR BELT TENSIONING APPLIANCE Filed Aug. 29, 1921 atented Jan. 259, 1924.

NIT

PAUL SPILGER, OF IlERANKFORT-ON-THE-MAIN, GERMANY.

. F MOTOR BELT-TENSIONING APPLIANCE Application filed August 29, 1921. Serial No. 496,609.

(GRANTED UNDER THE PROVISIONS OF THE ACT OF MARCH 3, 1921, 41 STAT. L., 1813.)

To all whom it may concern:

Be it known that I, PAUL SPILGER, a

. citizen of the German Republic, residing at Frankfort-on-the-Main, Germany, have invented certain new and useful Improvements Relating to Motor Belt-Tensioning Appliances (and for which I have obtained patents in Germany No. 331,813, filed Mar. 11, 1919; in Great Britain, No. 147 ,223, filedJuly 7, 1920; in Holland, No. 7,931, filed Aug. 14, 1920; in France, No. 527,147, filed July 8, 1920; in Norway, No. 35,821, filed July 10, 1920; in Switzerland, No. 91,648, filed July 9, 1920; in Denmark, No. 28,806, filed July 30, 1920), of which the following is a specification.

This invention relates to improved means for maintaining a desired or proper tension in a motor driving belt when this is arranged vertically or nearly so, and is in use, and also for releasing the belt from tension when not in operation. The object of the invention is to minimize the stretching of a belt by a proper adjustment of the tension therein.

The invention consists in an improved support for carrying the motor, the support comprising a base plate or frame supported on springs, the tension of which is varied according to the stretch of the belt, and a loading device which renders-it possible to maintaln on the belt the tension most suitable for the load it has to transmit. The motor base plate is connected to a sub-base or floor by means of pairs of double links which prevent the base plate from tilting through the belt-pull acting on one side of the motor.

The loading device may consist of a rotatably mounted shaft carrying an actuating disk and connected, with the base late by I means of a crank and link device, t e links being attached at one end to the crank on the shaft, and at the other end to the base plate. When a lever which is arranged to rotate the disk and to which a weight is adjustably or otherwise attached makes the disk and the shaft revolve, the base plate, with the motor resting on it, is lowered by the crank and link device until the desired belt tension is obtained.

The disk carries on its outer surface a pin which is adjustable in position in any one of a number of holes gm concentrically with the shaft, and on this pin the lever rests. By changing the position of the pin on the disk it is pOSSlble to maintain the lever in an approximately horizontal position, even if the disk should be turned through a considerable angle or distance.

Instead of connecting the shaft to the base plate by the crank and link device for shifting the position of the plate, other appropriate means may be employed, for instance, a rack attached to the base plate and cooperatively disposed between a suitably supported guide roller and a toothed pinion on the shaft may be employed.

A second pin is arranged preferably on the disk at a point which may be diametrically opposite the one on which the lever rests during the operation of the motor. By turning the lever over on to this second pin the belt can be released from tension so that no stretch of the belt can take place whilst the plant is at rest.

An example of the invention is shown-in the accompanying drawing, in which Fig. 1 is a front elevation of the motor base plate and sub-base and parts carried by them.

Fig. 2 is a side elevation; and

Fig. 3 a plan of the same.

Fig. 4 corresponds to Fig. 1, but shows the lever in a position when it becomes necessary to turn it back towards the horizontal b changing the pin in the disk to another ole.

The support for the motor mas shown, consists of upper channelor other-shaped frame members 0.. Similar lower members a and one or more cross members such as d. The members a and a are connected by means of bolts 6. The bolts pass through clearance holes in the upper frame members. Above and below these members the bolts carry lower and upper spiral springs f, f which tend to lift the base plate or frame a and therefore the motor. Suitable means such as the nuts f may be provided for adjusting the set of the springs. In

order that the base a and therefore the motor, may not take up an inclined position under the effect of the one sided belt pull, the pairs of links p connecting the upper and lower members a, a together, are provided.

From a cross member (1 of the upper p be changed to any frame links e, e are suspended. These links are connected at their power end, by means of. a bolt, to a crank g fixed to one end of the shaft 7: which is supported in bearings 71. On a squared portion at the other end of this shaft a disk n is non-rotatably at tached.

Mounted to pivot on shaft is in front of the disk 11. is a lever which carries a weight g which may be ma e adjustable in position lengthwise of the lever. The lever may be retained on the shaft is by means of a nut h and is supported intermediate of its ends by a pin r screwed into or other-wise supported on, the disk n. The position of the pin can of the holes 0 provided on the disk.

After the. motor is started lever g is brought into the position shown on Fig. 1, and tension is thereby put on the belt a. In case the belt should stretch in course of time,

the tension on the lower springsj is some-' what reduced so that the frame a is able to takea lower position, while-lever 9 may assume a lower position as shown on Fig. 4.

In any case, in order to prevent the lower member from contacting with the floor on,

gwhich the support rests and so be put out of "action, the'pin r on which the lever is seated should be removed from the hole in which it isat themoment inserted, and be placed in j oneof the higher holes 0 on the disk 02. so f "a jtozsupport the lever in a nearly horizontal "1 position;

In order to release the belt from tension, when-the motor is not running, a second series of holes 0' is arranged on the disk ndianietrically .op osite the series 0 for the receptionof a'pm 'r on to which thelever can be turned in order to release the tension in the'ibelt in. consequence of the lifting of the upper frame a in conjunction with the motor.

to keep 1. An improved support for a motor to maintain a proper tension in a motor driving belt, arranged vertically or nearly so, and for releasing the belt from tension when not in operation comprising in combination a base plate, vertical springs supporting said base plate and a device for shifting the base plate against the action of the springs so as the belt in uniformtension whilst the motor is running.

2. An improved support for a motor to maintain a proper tension in a motor driving belt, arranged vertically or nearly so, and for releasing the belt from tension when not in operation comprising in combination an upper and a lower base member, screwed bolts for connecting said members, springs on said bolts for carrying the upper base,

and links connecting the upper and lower base members to prevent the motor from tiltingunder the efl'ect 'of the one-sided belt pull, and a lever and weight for operating a base plate, a rotatably mounted shaft, a-

crank and link mechanism connecting the shaftand base plate, and a disk that is rigid with the shaft, a lever and weight for re 'volving said disk and thereby causing the base plate to be lowered until the belt is sufficiently tensioned for the power transmission required.

In testimony whereof I aflix my signature in presence of a witness.

- PAUL SPILGE-R. Witness BERNHARDT RmsER. 

